Safety of a new variety of barley for participants with coeliac disease

The study is a dietary intervention trial during which participants with coeliac disease will be randomly assigned to one of two treatment groups and will consume daily for 8 weeks a serve of either the ultra low gluten (ULG) barley or a gluten-free (GF) control cereal. The amount of gluten ingested in the serve of ULG barley is about is 0.3mg; the amount of gluten in a sealed bag of cereal containing 11 serves is 3.3mg. Over the last 15 years CSIRO has developed barley varieties with nearly undetectable gluten levels. In the hull-less variety we are examining in this clinical trial the level of gluten is so low (<5 ppm [parts per million]) that foods made exclusively from it would qualify as ‘gluten free’ under European and US international standards where foods containing less than 20 ppm gluten can carry that label. However in Australia due to the different legislative requirements foods here suitable for coeliac disease must be completely gluten free. A hulled variety of ULG barley is being cultivated commercially in Australia and used and sold in Germany in gluten-free beer (http://www.pionier-glutenfrei.de/). A healthy, high fibre grain safe for coeliacs and those avoiding gluten has significant potential to improve the diet of those individuals. This study involves scientific and clinical staff from CSIRO and Flinders Medical Centre (FMC) Department of Gastroenterology. Participants will be screened at FMC to ensure they are healthy and avoiding gluten, and will attend information sessions with a clinical trial co-ordinator to discuss the study, and a research dietitian to explain the nutritional aspects of the study. Both these sessions will take about an hour each. During the first information session (and after consenting to participate) the participants will provide a blood sample which will be used to check they are generally healthy, and that their coeliac antibodies indicate they are not likely to be eating gluten. When the results are received from the laboratory the co-ordinator will contact the participants and if they are eligible arrange the information session with the dietitian. During the second information session the dietitian will discuss the dietary aspects of the study, the faecal collections and provide a booklet of instructions. They will also arrange for a portable freezer, faecal collection kits, investigational product (including serving size instructions) and kitchen balance to be delivered to the participant's home. Participants will be asked to eat their serve of investigational product at breakfast when it can be mixed with fruit/yoghurt/milk/other cereal. If an individual can not eat their whole serve at breakfast they can divide their serve and eat at two meals each day during the entire study. During the first week the participants are advised to gradually introduce the new cereal to their diet (instructions provided) to enable their gut and microbiome to adjust to the changes in their diet. The dietitian will advise participants how to substitute the investigational product for carbohydrate-based foods containing similar amounts of energy to ensure weight changes for individuals during the study are under 3kg. When not consuming their investigational product the participants eat their normal, gluten free diet. On two occasions (V1, V2) participants will undergo an endoscopy to enable biopsy of the duodenum. This will be done before the dietary intervention starts (V1), and again at the end of the 8 week intervention (V2). These biopsies will enable the assessment by a pathologist of the health of the lining of their duodenum. Participants will make two 48 hr faecal collections during the study to enable the effects of the cereals on gut health to be assessed (before V1 and V2). Participants will complete questionnaires about any possible gluten ingestion during the study, and questionnaires to assess any symptoms they may experience. They will also complete a compliance diary and will return the empty plastic bags and uneaten investigational product at the end of the 8 week intervention. Participants will initially attend FMC for the two information sessions, and then either FMC or Noarlunga Hospitals on two occasions for their endoscopies. Participants will give blood (for coeliac disease serology and health screening) twice (first screening visit, and V2). Participants who complete the study will be given $200 vouchers to compensate for inconvenience and time the study required, and those who complete the first endoscopy will be provided a $50 voucher. Parking and reasonable travel costs will also be reimbursed.